President Obama's signature legislative achievement, the Affordable Care Act, has been off to what can be described, at best, as a rocky start.

Thanks to a terribly designed website, far from the Amazon.com-like experience promised by the administration, the first day of open enrollment saw a grand total of six people enroll. By day two, that number had jumped exponentially to an "astounding" 248.

Glitches, crashes, problems with the payment system and all sorts of other tech failures have led to the administration paring down its estimate of 7 million enrollees by the end of March.

Yet for all of Obamacare's rollout misfortunes, Republicans' hopes that the law collapses into a flaming, actuarial death spiral are unrealistic and politically dangerous.

By 2018, the Congressional Budget Office estimates that about 25 million people will have exchange-purchased coverage -- 20 million with subsidies. This represents slightly more than 8 percent of the projected total insured population -- a small but not insignificant share. Add in the beneficiaries of Obamacare's Medicaid expansion and you've a small but powerful constituency that will fight tooth and nail to protect its newly bestowed entitlements.

Moreover, the law takes many lessons from Republican health reforms ó the high deductibles allowed with many of the plans (as high as $6,350 for Bronze plans), for instance, encourage greater consumer cost-sharing; this is an undeniably conservative principle.

All of this isnít to say that that Obamacare is perfect. There are major problems with the law, including disincentives to work and unnecessary burdens on businesses.

Bureaucratic micromanagement of plan design has led to premiums skyrocketing in some areas at the same time as physician networks have tightened.

And, for the most part, those who donít qualify for subsidies or who qualify for a paltry subsidy (say, $10 or $20) will either be on the hook for an expensive plan they donít want or will have to pay a penalty to avoid getting coverage.

For many young, relatively healthy people, the choice between expensive (even if subsidized) coverage and paying the penalty will be simple ó the penalty will often pale in comparison to the cost of premiums and deductibles they would otherwise be paying.

Indeed, had Obamacare been passed with bipartisan support, itís likely that some of these pitfalls could have been addressed early on.

Instead, the administration and congressional Democrats engaged in closed-door negotiations, and rather than engaging in honest debate about the law, used back-of-the-envelope calculations (the typical family wonít save $2,500 under Obamacare) to make claims about it that even left-of-center analysts knew were false.

Republicans aren't innocent in all of this, however. Indeed, much of the past four years were spent railing against the law and voting 40 times to repeal it, without (until recently) bringing forth a credible plan to fix America's badly broken health care system.

The lesson is this: all entitlement programs need fixes.

The Great Society-era programs have all gone through changes, fixes, alterations and amendments. Medicare Part D and Medicare Advantage, some of the more recent additions to the Great Society programs, are favorites even of Republican politicians, thanks to their clever use of market mechanisms to deliver government benefits.

Obamacare is no different. Changes are, and always will be, necessary.

The onus is on both parties to help make these fixes possible ó the president and Senate Democrats will need to allow Republican compromises to the law, and Republicans will need to accept that Obamacare is here to stay and leverage the lawís framework to propel conservative reforms.

With luck, such bipartisanship can offer more affordable coverage to those who need it while also tackling the systemís real problems of cost and transparency.